Steam-engine.



LE GRAND SKINNER & E P. WILLIAMS.

STEAM ENGINE.

APPLICATION FILED SEPT. 30, 1911.

1,033,280. Patented July 23, 1912.

Witnesses. ITIVETILDIS L11 GRAND SKINNER & 11. 1". WILLIAMS.

STEAM ENGINE.

APPLICATION FILED SEPT. 30, 1911.

Patented July 23, 1912.

2 SHEETSSHBET 2.

'urirrnn s ATEs PATENT OFFICE.

LE GRAND SKINNER AND EDWIN F. WILLIAMS, OF ERIE, PENNSYLVANIA, .AS SIG-NORS TO SKINNER ENGINE COMPANY, OF ERIE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

STEAM-ENGINE.

Patented July 23, 1912.

Application filed September 30, 1911. Serial 1V0. 652,086.

have jointly invented certain new and use-' ful Improvements in Steam-Engines; and we do hereby declare the following to be a full, clear, and exact description of the 1nvcntion, such as will enable others skilled in.-

the art to which it appertains to make and use the same, reference being had to the accompanying drawings, mid to the letters of reference marked thereon, forming part of this specification.

This invention relates to improvements in steam-engines of the type in which the working steam enters the cylinder at the ends thereof arid exhausts through ports at the center of the cylinder which are uncovered by the piston atand near the end of its working stroke. and it consists substantially in providing the cylinder with main exhaust ports between the ends of the cylinder and the central exhaust ports therein, located at points approximately thirty percent. of the length of the workingv stroke of the piston from the ends of the cylinder, and valves for said. main exhaust ports operating to open said ports after the central exhaust port is opened and close said ports after the piston has covered them on its return stroke and thereby heavy pressures on the main exhaust valves during their operation are eliminated.

The objects and advantages of this improvement are as follows, viz: that comparatively small clearances are required at the ends of the cylinder, as during the return stroke of the piston the steam continuously exhausts through the main exhaust ports, until they are covered by the piston on its return stroke, and only the steam romainiug in the cylinder between the main 4 exhaust ports and the 0nd of the cylinder is utilized to provide the compression necessary to tillthe small clearances remaining when the return stroke of the piston is completed.

Another result of this construction is the thermal advantage gained from exhausting the colnparutivcly coolcxpandcdsteam without passing it over the heated ends of the cylindciz.

.'\ further objectand advantage of this engine, it only being necessary in the latter case to disconnect the mechanism 'whichopcrates the main exhaust valves, so that they will remain inoperative.

These and other features'of this invention are hereinafter fully set forth and ex-i plained andillustrated in the accompanying drawings, in which:

Figure 1 is a vertical central section on the line mw iii-Fig. 2 of a steam engine cylinder embodying this invention. Fig. 2 is a transverse section of the same on the line y'y in Fig. 1, showing one of the valves of the ma n exhaust'portsinclosed position. Fig. 3 is a detail showing one of the main exhaust valves in 'open'position. Fig. 4: is a detail showing a top or plan view of one of the main exhaust valves.

In these drawings A, indicates a steam engine cylinder, B, inlet ports at the. ends of the cylinder controlled by inlet valves B, operated by convenient valve-gear (not shown). The cylinder A, is provided with the usual reciprocatin piston C, and with central exhaust ports A, adapted to be uncovered by the end of the piston C, at and near the end of its stroke, which ports A,

, from the ends of the cylinder. These main exhaust ports are provided preferably with meclnlnically operated valves D, preferably of the slide-valve type. For operating these main valves we provide convenient valvegcar I) E which communicates with and is operated by ordinary valve-gear mechanism (not shown). The valve-gear E E geferably communicating with the valves by means of cam-slots e, engaging rollers d, on the valve-stein d, of said valves, whereby an intermittent motion is given to the valves I). 3 The preferred construction of the valves 1), and their valve seats D is cylindrical in form and contour, as illustrated in Fig. 4, so that the valve D, and its seats D will removably fit into cylindrical chambers F, in the lower part of the cylinder A. The valve-seats D are also provided with transverse exhaust passages (Z (Z com-.

opened or closed by operating the hand Wheels G G, whereby should water accumulate 1n the cyhnder while it is standing cold, the same may be drained away if desired. I In operation the valves D, are normally closed as illustrated in Fig. 2, during the working traverse of the piston C, and until the piston uncovers the central ports A, when the valve D, in the end of the cylinder being traversed by the return stroke of the piston is opened and the steam then exhausts tl'irough the main exhaust ports I), into the exhaust chamber A, and the valve D, remains open until the auxiliary ports 1), are covered by the piston C, when the valve D, is closed and remains closed dur- .ing the working stroke of the piston.

The advantages and results of the location and operation of the main exhaust ports 1),

in conjunctionwith the central exhaust ports A, is economy in steam consumption, increased elhciency theretrom, and thermal advantage troin exhausting the cool steam without contact with the heated end portions of the cylinder, and the comparatively small clearance required.

It will be n'ianit'est to those skilled in the art that while the main exhaust ports and valves have been hereinbetore shown and described as being located approximately thirty percent. of the stroke from each end of the cylinder, that considerable variation in the location of said ports and valves from that shown and described herein may exist without departing from the spirit of our invention.

cylinder and said central exhaust ports, of

valves for opening and closing said main exhaust ports, and valve-gear adapted to mechanically open and close said valves at periods when said valves are free from pressure substantially asset forth.

2. The combination in a steam engine, of a cylinder having a central exhaust port, and main exhaust ports located between said central exhaust and each end of the cylinder, a piston adapted to uncover the central exhaust port at and near the end of'its working stroke and to cover the main exhaust ports during the first part of its working stroke and the latter part of its return stroke, valves for said main exhaust ports, and valve gear adapted to open said valves after the central exhaust is opened and close them after the main exhaust ports are covered. by the piston on its return stroke, substantially as set forth. 7

3. The combination in a steam engine, of a cylinder having inlet ports at its ends, central exhaust ports and main exhaust ports located between said central exhaust port.

and each end of the cylinder, valycs and valve-gear for controlling said inlctports, a piston operatingv to uncover the central exhaust ports at and near the end of its working stroke and to cover the main exhaust ports during the first part of its work-' ing stroke and the latter part of its return stroke, valves for opening, and closing the main exhaust ports, and valve-gear operating to open the main exhaust ports after the central exhaust ports are opened and retain them open until the return stroke of the piston covers the main exhaust ports, and then close said valves and retain them closed until the central exhaust ports are again opened, substantially as set forth.

In testimony whereof We ailix our signatures, in presence of two witnesses.

lil GRAND SKTNNER. EDW'TN F. WILLIAMS.

Vitncsses l V. Glrronn, H. M. S'runonon. 

